Improved Barrage

From wow.incgamers.com

Talent: Improved Barrage
Effect: Increases the critical strike chance of your Multi-Shot ability by a % and gives you a % chance to avoid interruption caused by damage while channeling Volley.
Statistics: Rank 1 = Multi-Shot +4% critical strike chance and +33% chance to avoid interrupt on Volley, Rank 2 = Multi-Shot +8% critical strike chance and +66% chance to avoid interrupt on Volley, Rank 3 = Multi-Shot +12% critical strike chance and +100% chance to avoid interrupt on Volley.